Two of the greatest cinematic boxers of all time are getting ready to go one-on-one in a new movie, as Warner Bros. has officially given the greenlight to Grudge Match, an upcoming pugilist picture starring Robert De Niro (a.k.a. Jake La Motta from Raging Bull) and Sylvester Stallone (a.k.a. Rocky Balboa from Rocky).

Details about the project first arrived in June when it was also announced that Get Smart and Anger Management director Peter Segal had signed on to helm, and now Deadline has gotten news that not only is the film a go, but that it has added a new name to the cast. Kevin Hart, who has had a big year in 2012 so far with roles in movies like The Five-Year Engagement and Think Like A Man, has signed on to play "the fight promoter who gets two retired brawlers back in the ring." Entourage creator Doug Ellin is currently working on the most recent draft of the script. At this time we don't know much about the script other than the fact that both De Niro and Stallone will be playing retired fighters who decide to have one final bought.

As Deadline points out, it will be interesting to see how this plays out on the physical side, as Stallone has kept up with action hero exercise regimen through the years, while De Niro has been showing more of his age in recent years. Then again, De Niro did famously gain 70 pounds when he was doing scenes for the end of Raging Bull, so many he still has it in him to do the reverse and get in scary shape for Grudge Match.